JP2015181287A - Medium access method for multi-user transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a medium access method for multi-user transmission.SOLUTION: A medium access method for multi-user transmission includes: a step of selecting a plurality of destination devices; a step including a step of starting an exchange with at least one of the plurality of destination devices and transmitting a message to at least one of the plurality of destination devices; and a step of choosing whether to perform multi-user, multi-input and multi-output (MU-MIMO) radio data transmission to at least some of the plurality of destination devices or make an entry into backoff time, on the basis of the result of the exchange.

Description

  The present invention relates to media access for multi-user transmission.

  Media access techniques are used by wireless networks to provide devices with access to communication media. For example, in a wireless local area network (WLAN) defined by the IEEE 802.11 standard, a protection procedure for reserving a wireless medium for transmission of pending data can be used.

  This protection procedure uses a frame exchange method, in which a transmission apparatus and a reception apparatus exchange a transmission request (RTS) frame and a transmission clear (CTS) frame with each other. Alternatively, the device exchanges short data frames (e.g., QoS-Null) and acknowledgment (ACK) frames. These frames distribute network allocation vector (NAV) information (which indicates the transmission time length) to both the transmitting device and the receiving device. When the exchange is completed, the transmitting device transmits to the receiving device.

  In downlink multi-user transmission, data is transmitted to a transmission device (for example, an access point) and a plurality of reception devices (for example, STA). In general, however, current media access approaches utilize protection procedures that only work for one user at any time.

  A method according to an embodiment includes selecting one or more destination devices of a plurality of destination devices, and an exchange response from at least one destination device of the selected one or more destination devices. And, based on the obtaining step, selecting whether to perform wireless data transmission or to enter a back-off time, wherein the wireless data transmission is performed by at least one destination device of the plurality of destination devices. Including data.

  According to another embodiment, an apparatus includes a selection module that selects one or more destination apparatuses from among a plurality of destination apparatuses, and one or more that requests a response from a selected destination apparatus to which each corresponds. A transceiver module for transmitting a message and a determination module for selecting whether to transmit wireless data or to enter a back-off time based on a response result to the one or more messages. When it is selected whether to enter a back-off time, the transceiver module transmits the wireless data.

  A product according to yet another embodiment is a product having a machine-accessible medium having instructions stored thereon, wherein when the instructions are executed by the machine, the machine has one of a plurality of destination devices or Selecting a plurality of destination devices, obtaining an exchange response from at least one destination device of the selected one or more destination devices, and performing wireless data transmission or back-off time based on the obtaining step The wireless data transmission includes data of at least one destination device of the plurality of destination devices.

In the drawings, like reference numbers indicate identical, functionally similar, and / or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit of the element's reference number. The present invention will be described with reference to the accompanying drawings.
It is a figure which shows an operation environment example. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows the example of exchange between radio | wireless communication apparatuses. It is a figure which shows a logic flow example. 1 is a diagram illustrating an embodiment of an apparatus. 1 is a diagram illustrating an embodiment of an apparatus.

  As an embodiment, a technique related to media access is provided. For example, the transmission device has data to be transmitted to the destination device. The sending device selects one or more destination devices and initiates an exchange with each of the selected one or more devices. Based on the result of such exchange, the transmission device selects whether to transmit data or to enter a back-off time. The data transmission has data destined for the destination device.

  As used herein, “one embodiment” means that at least one embodiment includes the functions, structures, and features described with respect to that embodiment. In various places in this specification, “in one embodiment” is described in various places, but all are not necessarily referring to the same embodiment. Further, the functions, structures, or features may be combined as appropriate in one or more embodiments.

  The method described here will be described in the case of an IEEE 802.11 wireless local area network (WLAN). However, these methods are not limited to such a network. Thus, these techniques can be used with various network types. Examples of such networks include an IEEE 802.15 wireless personal area network (WPAN), such as a Bluetooth network. These methods may be used in the WiGig network. The WiGig network is a 60 GHz network defined by the Wireless Gigbit Alliance (eg, in the WiGig specification version 1.0). Another example network includes an IEEE 802.16 wireless metropolitan area network (WMAN), such as a WiMAX network. The WiMAX network supports directional transmission with a beamforming function. Further, the technique described here can be used in a millimeter wave (for example, 60 GHz) network. In addition, these approaches can be used in various cellular and / or satellite networks. These networks are described as examples and not as limitations. Thus, the techniques described here can be used with other network types.

  FIG. 1 is a diagram showing an example of an operating environment 100, and the method described here can be used in this environment. However, embodiments are not limited to this environment. The environment of FIG. 1 includes a plurality of wireless communication devices. More specifically, these devices include an access point (AP) 102 and a plurality of radio stations (STAs) 104a-c. In addition, these STAs are identified as STA1, STA2, and STA3 in FIG.

  The apparatus of FIG. 1 can utilize multi-user transmission. Multi-user transmissions include data destined for multiple receiving devices (eg, information related to one or more applications). For example, FIG. 1 shows that the AP 102 makes a downlink (DL) multi-user transmission 120 to STA1, STA2, and STA3. Specifically, FIG. 1 shows that the multi-user transmission 120 includes a portion 122a destined for STA1, a portion 122b destined for STA2, and a portion destined for STA3. Each portion 122a-c includes a header portion and a payload portion. For example, in an embodiment, each portion includes a data frame that is addressed to a corresponding receiving device.

  In embodiments, transmissions (such as multi-user transmission 120) are transmitted using multiple-input multiple-output (MIMO) and / or space division multiple access (SDMA) techniques. For example, transmission 120 is a multi-user MIMO (MU-MIMO) transmission. Accordingly, each of AT 102 and STA 104a-c has one or more antennas. Further, such transmissions may be formatted by orthogonal frequency division multiplexing (OFDM) techniques and / or orthogonal frequency division multiple access (OFDMA) techniques. However, embodiments are not limited to these examples.

  As described herein, a transmission device (for example, an access point) has data to be transmitted to a plurality of destination devices (for example, a plurality of STAs). Embodiments provide media access techniques that address such situations. Furthermore, embodiments provide a technique for handling errors that may occur with such a media access technique. Such a technique can be used in the environment of FIG. However, the embodiment is not limited to this case.

  In an embodiment, the transmitting device can select one or more destination devices among a plurality of destination devices involved in the exchange. For example, the transmission device may select all destination devices. Alternatively, the transmission device may select one destination device. The transmitting device is involved in exchange with one or more of the selected destination devices.

  In the exchange, the sending device sends a Ready to Send (RTS) frame and waits to receive a corresponding Clear to Send (CTS) frame from the selected destination device. Alternatively, in an exchange, the transmitting device transmits a short or empty data frame (eg, a QoS-Null frame) and waits for a corresponding acknowledgment (ACK) frame from the selected destination device. However, embodiments are not limited to the frames listed in these examples.

  Based on the result of such exchange, the transmitting device transmits including data to send to various combinations of destination devices (eg, one or more destination devices). Alternatively, the transmission device may not perform such transmission based on the result of such exchange. For example, the transmitting device waits for a backoff time (eg, an exponential backoff time). Following this back-off time, the transmitting device attempts transmission again. More specifically, the transmitting device selects the destination device again, participates in the exchange with the selected device, and potentially transmits based on the result of such exchange.

  An example of the method will be described below with reference to FIGS. These drawings show the interaction between the devices shown in FIG. However, such exchange is not limited to the case of FIG.

  FIG. 2 is an example in which one destination device is selected. Specifically, the AP 102 selects the STA 3 and transmits an RTS frame 220 thereto. In response to this, the STA 3 transmits a corresponding CTS frame 222. Upon receiving the CTS frame 222, the AP 102 performs data transmission 224. As shown in FIG. 2, the data transmission 224 includes data to be sent to each destination device (that is, each of STA1-STA3). The data transmission 224 includes a header (H) portion corresponding to each data portion.

  Upon receiving the data transmission 224, the destination device transmits a block acknowledgment (BA) to the AP 102. For example, FIG. 2 shows that STA1, STA2, and STA3 transmit BA226, BA228, and BA230, respectively.

  FIG. 3 is an example in which a plurality of destination devices are selected. Specifically, the AP 102 selects STA1 and STA3. Therefore, the AP 102 transmits the RTS frame 320 to the STA1, and transmits the RTS frame 322 to the STA3. In response, STA1 and STA3 transmit corresponding CTS frames 324 and 326, respectively. The AP 102 successfully receives these CTS frames. Therefore, the AP 102 performs data transmission 328. FIG. 3 shows that the data transmission 328 includes data to be sent to each destination device (ie, each of STA1-STA3). In addition, the data transmission 328 includes a header (H) portion corresponding to each data portion. FIG. 3 shows that STA1, STA2, and STA3 transmit BAs 330, 332, and 334 to the AP 102 in response to the data transmission 328.

  As described herein, messages other than CTS frames and RTS frames may be used in the exchange. For example, FIG. 4 shows an example in which a QoS-Null frame and an ACK frame are exchanged. More specifically, in FIG. 4, STA 2 and STA 3 are selected by the AP 102. Based on this selection, the QoS-Null frame and the ACK frame 420-426 are exchanged. Next, the AP 102 performs data transmission 428 to the STA1 to STA3. In addition, BAs 430, 432, and 434 are received from STA1, STA2, and STA3, respectively.

  As described above, the transmitting device (eg, AP) selects one or more destination devices to exchange. This selection may be made at random. This selection may be performed deterministically (for example, the transmission device may select all destination devices). Further, in some embodiments, the transmitting device may select a destination device that has been flagged.

  For example, if the transmission device does not receive the expected response from the destination device, the transmission device sets a flag for the destination device (flag). Examples of expected responses include, but are not limited to, exchange responses (eg, CTS frames, ACK frames, etc.) and acknowledgment messages (eg, BA frames).

  In the embodiment, the transmission device selects the destination device for which the flag has been set. From now on, the transmitting device starts exchanging with the selected destination device. As described above, this may include sending an RTS frame or a QoS-Null frame to the selected destination device.

  Thus, in some embodiments, a transmitting device exchanges with a destination device if it can communicate. This can advantageously streamline the exchange process associated with multi-user transmission by focusing on destination devices with potential problems.

  As described herein, various error handling techniques are provided by the embodiments. Such a technique is used, for example, when a failure occurs in exchange with one or a plurality of destination devices (for example, RTS / CTS exchange or QoS-Null / ACK exchange).

  In the first error handling technique, the transmitting device initiates an exchange (eg, RTS / CTS exchange, QoS-Null / ACK exchange, etc.) with each of the selected destination devices. In the first technique, the transmission device proceeds with pending data transmission as long as it receives an exchange response from at least one destination device of the selected destination devices. However, in this data transmission, data destined for a destination device that does not respond is excluded. Further, the transmission device may set a flag for a destination device that does not respond.

  5 and 6 show examples of this method. In FIG. 5, the AP 102 selects STA3 and STA2. Therefore, FIG. 5 shows that the AP 102 transmits a QoS-Null frame 520 to the STA 3 and transmits a QoS-Null frame 522 to the STA 2. AP 102 receives response ACK 524 from STA 2, but does not receive a response from STA 3. In FIG. 5, “X” shown in STA3 indicates this defect.

  Based on this result, FIG. 5 shows where the AP 102 performs multi-user transmission 526. This rent includes data destined for STA1 and STA2. However, since the AP 102 does not receive a response from the STA 3, the data of the STA 3 is excluded. FIG. 5 shows that in response to transmission 526, STA1 and STA2 transmit BA 628 and BA 630, respectively. Further, in the example of FIG. 5, the AP 102 flags the STA 3 because the STA 3 did not respond to the QoS-Null frame 520. Therefore, the AP 102 can select and exchange the STA 3 in the subsequent data transmission.

  FIG. 6 shows an example similar to FIG. However, in FIG. 6, RTS frames and CTS frames are used instead of QoS-Null frames and ACK frames. Specifically, FIG. 6 shows that the AP 102 transmits an RTS frame 620 and an RTS frame 622 to STA3 and STA2, respectively. Nevertheless, the AP 102 receives the response CTS frame 624 only from STA2. Based on this, the AP 102 performs data transmission 626 toward STA1 and STA2. In response to this data transmission, STA1 and STA2 transmit BA 628 and BA 630 to AP 102, respectively. Also, in this example of FIG. 5, the AP 102 can flag the STA 3 and select with subsequent exchanges related to data transmission.

  FIG. 7 is another example of the first error handling method, and shows a case where all the selected destination devices have not responded. In this example, the AP 102 selects STA3 and STA2. Therefore, the AP 102 transmits a QoS-Null frame 720 to the STA 3 and transmits a QoS-Null frame 722 to the STA 2. However, AP 102 receives no response for either frame. In FIG. 7, this defect is indicated by “X” shown in STA 3 and “X” shown in STA 2.

  Based on this, FIG. 7 shows that the AP 102 does not proceed to data transmission. This is because the AP 102 did not receive any response from the selected destination device. Thus, AP 102 waits for an exponential backoff time 724. Following this back-off time, the transmitting device attempts transmission again.

  In the second error handling technique, the transmitting device initiates an exchange (eg, RTS / CTS exchange, QoS-Null / ACK exchange, etc.) with one or more of the selected destination devices. . According to the second approach, the transmitting device refrains from pending data transmission if any one of the selected destination devices does not respond. This may include the transmitter waiting for a backoff time (eg, an exponential backoff time). Further, the transmission device may set a flag for a destination device that does not respond.

  FIG. 8 shows an example of the second error processing technique. In this example, the AP 102 selects STA3 and sends a QoS-Null frame 820 to it. However, AP 102 does not receive a corresponding response from STA3. As a result, AP 102 waits for an exponential backoff time 822. Following the backoff time 822, the AP 102 attempts to transmit again.

  FIG. 9 shows another example of the second error processing method. In this example, the AP 102 selects STA2 and STA3. Therefore, the AP 102 transmits a QoS-Null frame 920 to the STA 2 and transmits a QoS-Null frame 922 to the STA 3. The AP 102 receives the ACK frame 924 from the STA2. However, AP102 does not receive a response from STA3. Accordingly, AP 102 refrains from data transmission 328. This includes the AP 102 sending a CF-End frame 926 and waiting for an exponential backoff time 928. Following the backoff time 928, the AP 102 attempts to transmit again.

  Another example of the second error processing technique is shown in FIG. This example is similar to the example of FIG. However, in the example of FIG. 10, RTS frames and CTS frames are used instead of QoS-Null frames and ACK frames. Specifically, FIG. 10 shows that AP 102 transmits RTS frame 1020 and RTS frame 1022 to STA2 and STA3, respectively. However, AP 102 only receives a response CTS frame 1024 from STA2. Accordingly, AP 102 transmits a CF-End frame 1026 and waits for an exponential backoff time 1028. Following the backoff time 1028, the AP 102 attempts transmission again.

  In the third error handling technique, the transmitting device selects one or more destination devices for exchange (eg, RTS / CTS exchange, QoS-Null / ACK exchange, etc.). In the third method, the transmission device refrains from pending data transmission if it does not receive an exchange response (eg, CTS frame, ACK frame, etc.) from the first destination device among the selected destination devices. This may include the transmitter waiting for a backoff time (eg, an exponential backoff time).

  However, when the transmitting device receives an exchange response from the first destination device, it initiates an exchange with all of the remaining selected destination devices. Thereafter, the transmission apparatus performs pending data transmission. However, in this data transmission, data destined for a destination device that does not respond may be excluded. Furthermore, in the third method, the transmission device may set a flag for a destination device that does not respond.

  FIG. 11 shows an example of the third error processing method. In this example, the AP 102 selects one or more destination devices. The selected device includes STA3. Based on this, the AP 102 attempts a first exchange with the STA 3 by transmitting an RTS frame 1120. However, AP102 does not receive a corresponding response from STA3. Accordingly, AP 102 refrains from pending data transmissions and waits for an exponential backoff time 1022.

  FIG. 12 shows another example of the third error processing method. In this example, the AP 102 selects STA1, STA2, and STA3. Based on this, the AP 102 attempts a first exchange with STA1 by transmitting an RTS frame 1220. In response, the AP 102 receives the corresponding CTS frame 1222 from the STA1.

  As a result, AP 102 proceeds with transmission. Thus, FIG. 12 shows that the AP 102 transmits an RTS frame 1224 to the STA2. However, AP 102 does not receive a corresponding response from STA2. In spite of this, the AP 102 has received a response from the STA1 (first destination device), and therefore proceeds with transmission. Therefore, the AP 102 transmits an RTS frame 1226 to the STA 3. In response to this, the AP 102 receives the CTS frame 1228 from the STA 3.

  Based on these exchanges, AP 102 performs data transmission 1230. This transmission includes data destined for STA1 and STA3. However, since the AP 102 does not receive a response from the STA2, the data of the STA2 is excluded. FIG. 12 shows that in response to transmission 1230, STA1 and STA3 transmit BA 1232 and BA 1234, respectively.

  In the example shown in FIG. 2 to FIG. 12, the transmitting device starts exchange and waits for a response from the selected destination device. The transmitting device can use various time intervals to wait for the exchange response. For example, in the case of an IEEE 802.11 network embodiment, the transmitting device waits for priority inter-frame space (PIFS) time. If no response is received within this time, the transmitting device assumes that the exchange has failed. However, the embodiment is not limited to this example. Furthermore, the embodiment is not limited to the examples shown in FIGS.

  FIG. 13 is a diagram illustrating one embodiment of a logic flow. Specifically, FIG. 13 shows a logic flow 1300 that represents the operations performed by the above embodiment. These operations can be used in the environment of FIG. However, the embodiment is not limited to this case. FIG. 13 shows a specific order, but the order may be different. The illustrated operations can be executed in parallel or sequentially.

  In block 1302, the wireless communication device (also referred to as a transmission device) has data to be transmitted to a plurality of destination wireless communication devices. In an embodiment, the transmitting device may be an AP, and the plurality of destination devices may be STAs. However, the embodiment is not limited to this case.

  Accordingly, at block 1304, the transmitting device selects one or more destination devices. This choice is based on various factors. For example, all destination devices may be selected. Alternatively, one or more specific destination devices may be selected. For example, the transmitting device may select one or more destination devices that have not previously responded to the access point (eg, flagged).

  In block 1306, the transmitting device begins to exchange with at least one of the selected destination devices. This includes the exchange device seeking an exchange response from the selected destination device. This may involve, for example, sending a message (eg, RTS frame, QoS-Null frame, etc.) to the selected destination device and a corresponding response message (eg, CTS frame, ACK frame, etc.) from the selected destination device. Including waiting.

  In some embodiments, block 1306 includes the sending device initiating an exchange with each of the selected destination devices. However, in another embodiment, block 1306 includes the sending device beginning to exchange with some but not all of the selected destination devices. For example, if the sending device does not receive a response message as a result of a previously initiated exchange (eg, the first exchange initiated), the destination device may bypass the later exchange.

  In block 1308, the transmitting device determines the result of block 1306. Based on the result, the transmitter selects whether to transmit data at block 1310 or wait for a backoff time (eg, an exponential backoff time) at block 1312. This selection at block 1310 may be according to the techniques described herein.

  For example, according to the first error handling technique described herein, when a response is received from at least one destination device of the destination device for which the transmitting device was selected as a result of block 1306, the transmitting device selects to transmit data. . Thus, if the sending device does not receive an exchange response from all of the selected destination devices, it waits for a backoff time at block 1312.

  According to the second error handling technique described herein, when a response is received from all of the destination devices for which the transmitting device has been selected as a result of block 1306, the transmitting device selects (at block 1310) to transmit data. . Thus, if the sending device does not receive an exchange response from any of the selected destination devices, it waits for a backoff time at block 1312.

  However, the transmitting device may select to transmit data (at block 1310) upon receiving a response from the first destination device that the transmitting device sought for a response at block 1306. Thus, if the sending device does not receive an exchange response from this first destination device, it waits for a backoff time at block 1312.

  As described above, the transmitting device performs data transmission at block 1310. This data transmission may be wireless MIMO transmission and / or SDMA transmission. The data transmission includes data destined for one or more destination devices. However, in some embodiments, data transmission may exclude data addressed to a destination device that does not respond.

  Also, as described above, the transmitting device may wait for a backoff time at block 1312. The length of this back-off time is determined by the transmitter. FIG. 13 shows that operation returns to block 1304 after the backoff time. Therefore, the transmission device tries to achieve data transmission to the destination device again.

  FIG. 14 is a diagram illustrating an implementation 1400 included in a wireless device such as a STA and / or access point. As shown in FIG. 14, the implementation 1400 includes an antenna module 1402, a transceiver module 1404, a host module 1406, and an access module 1407. These elements can be implemented in hardware, software, or a combination thereof.

  The antenna module 1402 exchanges radio signals with the remote device. Further, the antenna module 1402 transmits a radio signal with one or more directional radiation patterns. As such, antenna module 1402 includes multiple antennas and / or multiple radiating elements (eg, phased array radiating elements). Details regarding an implementation example of the antenna module 1402 will be described with reference to FIG.

  FIG. 14 shows that the transceiver module 1404 includes a transmitter 1408, a receiver 1410, a control module 1412, and a directivity control module 1416. These elements can be implemented in hardware, software, or a combination thereof.

  The transceiver module 1404 provides an interface between the antenna module 1402 and the host module 1406. For example, the transmission unit 1408 in the transceiver module 1404 receives the symbol 1420 from the host module 1406, generates a corresponding signal 1422, and wirelessly transmits it via the antenna module 1402. This includes operations such as modulation, amplification, and / or filtering. However, other operations can be used.

  Conversely, the reception unit 1410 in the transceiver module 1404 acquires the signal 1424 received by the antenna module 1402. Next, the receiving unit 1410 provides the symbol 1426 to the host module 1406. Generation of symbol 1426 includes (but is not limited to) operations such as demodulation, amplification, and / or filtering.

  The symbols exchanged between the host module 1406 and the transceiver module 1404 constitute messages and information related to one or more protocols and / or one or more user applications. Therefore, the host module 1406 performs an operation corresponding to the protocol and / or the user application. Examples of protocols include various media access layer protocols, network layer protocols, transport layer protocols, and / or session layer protocols. Examples of user applications include telephony, messaging, email, web browsing, content delivery / reception, etc.

  The host module 1406 exchanges control information 1440 with the transceiver module 1404. This control information relates to the operation and status of the transceiver module 1404. For example, the control information 1440 includes instructions that the host module 1406 transmits to the transceiver module 1404. Such instructions establish operating parameters and characteristics of transceiver module 1404. In addition, the control information 1440 includes data (for example, operation state information) that the host module 1406 receives from the transceiver module 1404.

  As described above, the transmission unit 1408 generates a signal 1422 from the symbol 1420, and the reception unit 1410 generates a symbol 1426 from the received signal 1424. To provide such functionality, transmitter 1408 and receiver 1410 each include various components such as a modulator, demodulator, amplifier, filter, buffer, upconverter, and / or downconverter. Such components can be implemented in hardware (eg, electronics), software, or a combination thereof.

  There are various formats for signals 1422 and 1424. For example, these signals are formatted for transmission over an IEEE 802.11, IEEE 802.15, WiGig, and / or IEEE 802.16 network. However, embodiments are not limited to these networks.

  The control module 1412 manages various operations of the transceiver module 1404. For example, the control module 1412 establishes operating characteristics of the transmission unit 1408 and the reception unit 1410. Such characteristics include (but are not limited to) timing, amplification, modulation / demodulation characteristics, and the like. As shown in FIG. 14, the establishment of such characteristics is performed by instructions 1428 and 1430. These commands are sent to the transmission unit 1408 and the reception unit 1410, respectively.

  The control module 1412 manages the use of the directivity transmission / reception function. Specifically, FIG. 14 shows that the control module 1412 generates an instruction 1434 that is sent to the directivity control module 1416. Based on the instruction 1434, the directivity control module 1416 generates a setting parameter 1442. This setting parameter 1442 is sent to the antenna module 1402.

  The setting parameter 1442 specifies specific parameters to be applied to each antenna and / or radiating element in the antenna module 1402. Examples of such parameters include (but are not limited to) values such as amplification gain, antenna factor, and / or phase shift.

  The access module 1407 operates according to the access method described here. For example, the access module 1407 performs such a technique when the host module 1406 indicates that it has data to send to multiple destination devices. As shown in FIG. 14, the access module 1407 includes a selection module 1414, an exchange module 1419, and a determination module 1417.

  The selection module 1414 selects one or more destination devices in the manner described. Based on this, the exchange module 1419 seeks a response from one or more selected destination devices and generates an exchange message (eg, RTS frame, QoS-Null frame frame, etc.). Such a message is transmitted via the transceiver module 1404 and the antenna module 1402. Exchange module 1419 also receives corresponding responses via transceiver module 1404 and antenna module 1402.

  Based on the response received by the exchange module 1419, the decision module 1417 selects whether to send data or enter a backoff time. Such selection is performed by the method described here. Further, the decision module 1417 indicates such selection to the host module 1406. Then, the host module 1406 operates appropriately (for example, transmits or waits).

  FIG. 15 is a diagram illustrating an example of the antenna module 1402. As shown in FIG. 15, this embodiment includes a plurality of radiating elements 1502a-n, a plurality of processing nodes 1504a-n, a splitter module 1506, a combiner module 1507, and an interface module 1508. These elements can be implemented in hardware, software, or a combination thereof.

  Each radiating element 1502 is an individual antenna. Alternatively or additionally, each radiating element 1502 is a radiating element in a phased array antenna or a switched beam antenna. Thus, the radiating elements 1502a-n may be any combination of one or more individual antennas, one or more phased array antennas, and / or one or more switched beam antennas. As shown in FIG. 15, the radiating elements 1502a-n are each coupled to a corresponding processing module of the processing module 1504a-n.

  As shown in FIG. 15, splitter module 1506 receives signal 1422 (this signal 1422 was generated by transceiver module 1404 of FIG. 14). Upon receipt, splitter module 1506 “splits” signal 1422 to substantially the same input signal 1520a-n. A certain amount of insertion loss may occur in the split process. The splitter module 1506 performs operations such as amplification and / or filtering. Input signals 1520a-n are sent to processing nodes 1504a-n, respectively.

  Processing nodes 1504a-n generate processed signals 1522a-n from input signals 1520a-n, respectively. The processed signals 1522a-n are then sent to processing elements 1502a-n, respectively. Conversely, processing nodes 1504a-n generate processed signals 1523a-n from the radio signals received by elements 1502a-n. These signals are combined into a received signal 1424 by a combining module 1507.

  In generating the processed signals 1522a-n and 1523a-n, the processing modules 1504a-n perform various operations. Examples of such operations performed by processing nodes 1504a-n include (but are not limited to) attenuation, amplification, and / or phase shifting. Switching is yet another example of operation. For example, one or more processing nodes 1504a-n selectively pass or block corresponding signals.

  The manner in which processing nodes 1504a-n generate processed signals 1522a-n and 1523a-n is determined by control signals 1524a-n, respectively. Thus, these signals convey attenuation factors, amplification gains, phase shift values, switching commands, and the like.

  In some embodiments, control signals 1524a-n are included in configuration parameters 1442. Configuration parameters 1442 are received by interface module 1508. These parameters are received in a variety of formats (eg, analog, digital, serial, parallel, etc.). The interface module 1508 takes these parameters and formats them as control signals 1524a-n. As described above, the control signals 1524a-n are sent to the processing nodes 1504a-n, respectively.

  The implementation of FIG. 15 is for illustrative purposes and is not intended to be limiting. Therefore, the mounting of the antenna module 1502 may include other elements. For example, including one or more amplifiers and / or filters. Such amplifiers and / or filters are coupled between processing nodes 1504a-n and elements 1502a-n.

  As described above, embodiments may be implemented with hardware elements, software elements, or a combination thereof. Examples of hardware elements include processors, microprocessors, circuits, circuit elements (eg, transistors, resistors, capacitors, inductors, etc.), integrated circuits, ASICs, PLDs, DSPs, FPGAs, logic gates, registers, semiconductor devices, chips , Including microchips, chip sets and the like.

  Examples of software include software components, programs, applications, computer programs, application programs, system programs, machine programs, operating system software, middleware, firmware, software modules, routines, subroutines, functions, methods, procedures, software interfaces, applications A program interface, instruction set, computing code, computer code, code segment, computer code segment, word, value, symbol, or combinations thereof are included.

  Some embodiments, for example, using machine-readable media or articles that store instructions or a set thereof that, when executed by a machine, cause the machine to perform the methods and / or operations according to the embodiment. To be implemented. Such machines may include, for example, a suitable processing platform, computing platform, computing device, processing device, computing system, processing system, computer processor, etc., and suitable hardware and / or software combinations. May be used.

  Machine-readable media or products include, for example, any suitable type of memory unit, memory device, memory product, memory media, storage device, storage product, storage medium and / or storage unit, such as memory, removable or non- Removable media, erasable or non-erasable media, writable or non-writable media, digital or analog media, hard disk, floppy disk, CD-ROM, CD-R, CD-RW, optical disk, magnetic media, Includes magneto-optical media, removable memory cards or disks, various types of DVDs, tapes, cassettes, and the like. Instructions include source code, compiled code, interpreted code, executable code implemented using a suitable language such as high-level, low-level, object-oriented, visual, compiled, and / or interpreted programming languages , Any suitable code such as a static code, dynamic code, encryption code, etc.

  While various embodiments of the present invention have been described, it will be appreciated that these embodiments are illustrative and not limiting. For example, the method described here is not limited to downlink communication. Furthermore, the method described here is not limited to communication between the AP and the STA.

Accordingly, it will be apparent to those skilled in the art that various changes in form and detail can be made without departing from the spirit and scope of the invention. Therefore, the scope of the present invention is not limited by the above-described embodiments, but should be defined only by the following claims and their equivalents.
Additional notes will be made about the embodiment.
(Supplementary Note 1) Selecting one or more destination devices out of a plurality of destination devices;
Determining an exchange response from at least one destination device of the selected one or more destination devices;
Selecting whether to perform wireless data transmission or enter a back-off time based on the determining step;
The method wherein the wireless data transmission includes data of at least one destination device of the plurality of destination devices.
(Supplementary note 2) The method according to supplementary note 1, wherein selecting the plurality of destination devices includes selecting a destination device that has not responded previously.
(Supplementary note 3) The method according to supplementary note 1, wherein the step of selecting the plurality of destination devices includes the step of randomly selecting the one or more destination devices.
(Supplementary Note 4) If a response is received from at least one destination device of the selected one or more destination devices as a result of the obtaining step, whether to transmit the wireless data or enter a back-off time The method of claim 1, wherein the selecting includes selecting to perform the wireless data transmission.
(Supplementary note 5) The method according to supplementary note 4, wherein the wireless data transmission includes data of each destination device among the plurality of destination devices.
(Supplementary Note 6) If the response is not received from at least one of the selected one or more destination devices as a result of the obtaining step, whether to transmit the wireless data or enter a back-off time The step of selecting includes the step of selecting to transmit the wireless data;
The method of claim 1, wherein the wireless data transmission excludes data of at least one destination device of the plurality of destination devices.
(Supplementary Note 7) If a response cannot be received from one or more of the selected at least one destination device as a result of the obtaining step, whether to transmit the wireless data or enter a back-off time The method of claim 1, wherein the selecting includes selecting to enter the back-off time.
(Appendix 8) The step of obtaining
Transmitting an RTS frame to each of the selected one or more destination devices;
And waiting for a CTS frame from each of the selected one or more destination devices.
(Supplementary Note 9)
Transmitting a QoS-Null frame to each of the selected one or more destination devices;
And waiting for an ACK frame from each of the selected one or more destination devices.
(Supplementary note 10) The method according to supplementary note 1, wherein the back-off time is an exponential back-off time.
(Supplementary note 11) The method according to supplementary note 1, wherein the wireless data transmission is a space division multiple access (SDMA) transmission.
(Supplementary note 12) The method according to supplementary note 1, wherein the wireless data transmission is a multiple-input multiple-output (MIMO) transmission.
(Supplementary note 13) a selection module that selects one or more destination devices out of a plurality of destination devices;
A transceiver module that transmits one or more messages each seeking a response from a corresponding selected destination device;
A decision module for selecting whether to transmit wireless data or enter a back-off time based on a response result to the one or more messages;
An apparatus wherein the transceiver module transmits the wireless data when selecting to transmit wireless data or enter a back-off time.
(Supplementary note 14) If the response result includes receiving a response to the at least one message of the one or more messages, the decision module selects to transmit the wireless data; The apparatus of claim 13 that chooses to enter a backoff time.
(Supplementary note 15) If the response result includes receiving a response to all messages of the one or more messages, the decision module selects to transmit the wireless data; The apparatus of claim 13 that chooses to enter off-time.
(Supplementary note 16) The device according to supplementary note 13, wherein the selection module selects a destination device that has not responded previously.
(Supplementary note 17) The apparatus according to supplementary note 13, wherein the wireless data transmission is a space division multiple access (SDMA) transmission.
(Supplementary note 18) The apparatus according to supplementary note 13, wherein the wireless data transmission is a multiple-input multiple-output (MIMO) transmission.
(Supplementary note 19) A product having a machine-accessible medium storing instructions, wherein when the instructions are executed by a machine,
Selecting one or more destination devices of the plurality of destination devices;
Determining an exchange response from at least one destination device of the selected one or more destination devices;
Based on the step of obtaining, the wireless data transmission or the back-off time is selected,
The wireless data transmission is a product including data of at least one destination device of the plurality of destination devices.
(Supplementary note 20) The product according to supplementary note 19, wherein the step of selecting the plurality of destination devices includes a step of selecting a destination device that has not previously responded.

100 Operating environment 102 Access point (AP)
104 radio stations

Claims (16)

Selecting a plurality of destination devices;
Starting an exchange with at least one destination device of the plurality of destination devices, comprising sending a message to at least one destination device of the plurality of destination devices;
Selecting whether to perform multi-user multi-input multi-output (MU-MIMO) wireless data transmission or to enter a back-off time to at least some of the plurality of destination devices based on the result of the exchange. Method.   The method of claim 1, wherein the selecting comprises selecting a destination device that has not previously responded.   The step of selecting, when receiving a response from at least one of the plurality of destination devices by the step of transmitting the message, includes the step of selecting to transmit the MU-MIMO wireless data. The method according to 1.   The method of claim 3, wherein the MU-MIMO wireless data transmission includes data of each destination device of the plurality of destination devices. If the step of initiating the exchange cannot receive a response from at least one destination device of the plurality of destination devices, the step of selecting includes the step of selecting to transmit the MU-MIMO wireless data;
The MU-MIMO wireless data transmission excludes data of at least one destination device among the plurality of destination devices.
5. A method according to any one of claims 1 to 4.   The step of selecting if the step of initiating the exchange fails to receive a response from one or more of the plurality of destination devices, the step of selecting includes entering the back-off time. The method as described in any one of thru | or 4.   The method according to any one of claims 1 to 4, wherein the step of transmitting the message includes a step of transmitting an RTS frame to each of the plurality of destination devices.   The method according to claim 1, wherein the backoff time is an exponential backoff time.   The method according to any one of claims 1 to 4, wherein the wireless data transmission is a space division multiple access (SDMA) transmission. A selection module for selecting multiple destination devices;
A transceiver module that transmits a message to at least one of the plurality of destination devices;
A determination module for selecting whether to perform multi-user multi-input multi-output (MU-MIMO) wireless data transmission or to enter a back-off time based on a response result to the message. The transceiver module sends a message to a portion of the plurality of destination devices;
The decision module chooses to transmit the wireless data if the response result includes receipt of a response to the at least one message of the message, and otherwise enters the backoff time. Item 10. The apparatus according to Item 10. The transceiver module sends a message to all of the plurality of destination devices;
The decision module chooses to transmit the MU-MIMO radio data if the response result includes reception of responses from all destination devices of the plurality of destination devices; otherwise, at the back-off time. 12. A device according to claim 10 or 11, wherein one chooses to enter.   The apparatus of claim 10, wherein the selection module selects a destination device that has not previously responded.   The apparatus of claim 10, wherein the wireless data transmission is a space division multiple access (SDMA) transmission. When executed by a computer, the computer
Selecting one or more destination devices of the plurality of destination devices;
Initiating an exchange with at least one destination device of the selected one or more destination devices, wherein the initiation includes sending a message to at least one destination device of the plurality of destination devices;
Based on the result of the exchange, at least some of the plurality of destination devices may select whether to perform multi-user multi-input multi-output (MU-MIMO) wireless data transmission or enter a back-off time.
Computer program.   The computer program according to claim 15, which causes the computer to select a destination device that has not responded previously.

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